Hi Simon We've discussed this problem before--there is a post from last month called 'Binary problem' (Tue, 18 Jun 2002 15:33:56 +0100) which looks like the same thing. On reading that trail, it looks like it was fixed, though. You don't really say what release of mono you are running--0.12 would have the problem for sure, but snapshots from earlier this month should be ok. Regards Hinne